This invention relates generally to methods and apparatus for electrophoresis and more particularly relates to horizontal slab gel electrophoresis.
The most commonly used technique for separation and purification of colloidal particles is by vertical gel electrophoresis using either tubes or slabs. However, certain problems are inherent with a vertical slab gel electrophoresis apparatus. For example, for obvious reasons it has been impossible to use very low percentage agarose gels that are necessary to separate high molecular weight fragments. For such resolutions gels of much less than 0.7% are necessary and cannot be used in a vertical slab gel electrophoresis apparatus. Also the thickness and therefore the capacities of vertical gels have been limited because thick gels are difficult to support and the number of samples per gel is small, usually no more than twenty-five.
Many of the above problems can be eliminated by the use of horizontal rather than a horizontal electrophoresis apparatus. While there have been horizontal slab gel electrophoresis devices described they also suffer from some deficiencies. Among these are that previous devices have not been able to accommodate the variable size gels and there has been no visualization or manipulation of the gels during operation. Further, the use of paper wicks for contact with a running buffer or coolant has been a disadvantage because the wicks can dry out, reducing the conductivity and sometimes even tear. Also, maintenance of the buffer equilibrium and pH as well as maintaining constant voltage have also been problems with prior art devices. One prior art device does provide a horizontal plate for a gel, but does not provide any easy method to remove the gel and appears to be unsuitable for very soft or low percentage gels. All of the above problems with the horizontal and vertical slab gel electrophoresis devices can be eliminated by use of the horizontal slab gel electrophresis device disclosed herein.